electron/shell/common/gin_helper/promise.cc
trop[bot] 8d9ed52c72
perf: avoid redundant Promise.GetContext calls (#43620)
refactor: avoid redundant Promise.GetContext calls

Several Promise methods call `GetContext()` multiple times. From looking
at the assembly in obj/electron/electron_lib/promise.o, these redundant
calls are actually being made -- they aren't optmized out.

This PR keeps the return value in a local variable to avoid extra calls.

Co-authored-by: trop[bot] <37223003+trop[bot]@users.noreply.github.com>
Co-authored-by: Charles Kerr <charles@charleskerr.com>
2024-09-08 10:37:42 -05:00

110 lines
3.5 KiB
C++

// Copyright (c) 2018 GitHub, Inc.
// Use of this source code is governed by the MIT license that can be
// found in the LICENSE file.
#include <string_view>
#include "shell/common/gin_helper/promise.h"
#include "v8/include/v8-context.h"
namespace gin_helper {
PromiseBase::PromiseBase(v8::Isolate* isolate)
: PromiseBase(isolate,
v8::Promise::Resolver::New(isolate->GetCurrentContext())
.ToLocalChecked()) {}
PromiseBase::PromiseBase(v8::Isolate* isolate,
v8::Local<v8::Promise::Resolver> handle)
: isolate_(isolate),
context_(isolate, isolate->GetCurrentContext()),
resolver_(isolate, handle) {}
PromiseBase::PromiseBase() : isolate_(nullptr) {}
PromiseBase::PromiseBase(PromiseBase&&) = default;
PromiseBase::~PromiseBase() = default;
PromiseBase& PromiseBase::operator=(PromiseBase&&) = default;
v8::Maybe<bool> PromiseBase::Reject() {
v8::HandleScope handle_scope(isolate());
v8::Local<v8::Context> context = GetContext();
gin_helper::MicrotasksScope microtasks_scope{
isolate(), context->GetMicrotaskQueue(), false,
v8::MicrotasksScope::kRunMicrotasks};
v8::Context::Scope context_scope(context);
return GetInner()->Reject(context, v8::Undefined(isolate()));
}
v8::Maybe<bool> PromiseBase::Reject(v8::Local<v8::Value> except) {
v8::HandleScope handle_scope(isolate());
v8::Local<v8::Context> context = GetContext();
gin_helper::MicrotasksScope microtasks_scope{
isolate(), context->GetMicrotaskQueue(), false,
v8::MicrotasksScope::kRunMicrotasks};
v8::Context::Scope context_scope(context);
return GetInner()->Reject(context, except);
}
v8::Maybe<bool> PromiseBase::RejectWithErrorMessage(
const std::string_view message) {
v8::HandleScope handle_scope(isolate());
v8::Local<v8::Context> context = GetContext();
gin_helper::MicrotasksScope microtasks_scope{
isolate(), context->GetMicrotaskQueue(), false,
v8::MicrotasksScope::kRunMicrotasks};
v8::Context::Scope context_scope(context);
v8::Local<v8::Value> error =
v8::Exception::Error(gin::StringToV8(isolate(), message));
return GetInner()->Reject(context, (error));
}
v8::Local<v8::Context> PromiseBase::GetContext() const {
return v8::Local<v8::Context>::New(isolate_, context_);
}
v8::Local<v8::Promise> PromiseBase::GetHandle() const {
return GetInner()->GetPromise();
}
v8::Local<v8::Promise::Resolver> PromiseBase::GetInner() const {
return resolver_.Get(isolate());
}
// static
void Promise<void>::ResolvePromise(Promise<void> promise) {
if (electron::IsBrowserProcess() &&
!content::BrowserThread::CurrentlyOn(content::BrowserThread::UI)) {
content::GetUIThreadTaskRunner({})->PostTask(
FROM_HERE,
base::BindOnce([](Promise<void> promise) { promise.Resolve(); },
std::move(promise)));
} else {
promise.Resolve();
}
}
// static
v8::Local<v8::Promise> Promise<void>::ResolvedPromise(v8::Isolate* isolate) {
Promise<void> resolved(isolate);
resolved.Resolve();
return resolved.GetHandle();
}
v8::Maybe<bool> Promise<void>::Resolve() {
v8::HandleScope handle_scope(isolate());
v8::Local<v8::Context> context = GetContext();
gin_helper::MicrotasksScope microtasks_scope{
isolate(), context->GetMicrotaskQueue(), false,
v8::MicrotasksScope::kRunMicrotasks};
v8::Context::Scope context_scope(context);
return GetInner()->Resolve(context, v8::Undefined(isolate()));
}
} // namespace gin_helper